Hi,
In case that you didn't yet solve your problem: I experienced similar problems
when something was wrong with my articulated bodies - in my case it was never
related to contacts with the floor.
You also have to check all your articulated joints. For example, if your bodies
intersect (by mistake) when you create them (well I guess in your case that
doesn't matter since you don't collide them), and then you fix them together
with a joint, this obviously leads to strange results as taking off into the
sky.
Also when I had bugs in my joint position controller I observed things like
this... Refer to the previous thread 'joint position control' - I (and other
users) had problems when using controllers and setting joint limits.
Daniel
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Daniel Marbach
Bitziusstr. 9
CH-3006 Bern
Tel: 031 351 11 09
WWW: http://icwww.epfl.ch/~marbach/
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